Derivative Works
In examining a copy (or a record, disk, or tape) for copyright information, it is important to determine whether that particular version of the work is an original edition of the work or a "new version." New versions include musical arrangements, adaptations, revised or newly edited editions, translations, dramatizations, abridgments, compilations, and works republished with new matter added. The law provides that derivative works, published or unpublished, are independently copyrightable and that the copyright in such a work does not affect or extend the protection, if any, in the underlying work. Under the 1909 law, courts have also held that the notice of copyright on a derivative work ordinarily need not include the dates or other information pertaining to the earlier works incorporated in it. This principle is specifically preserved in the present copyright law. Thus, if the copy (or the record, disk, or tape) constitutes a derivative version of the work, these points should be kept in mind:
The date in the copyright notice is not necessarily an indication of when copyright in all the material in the work will expire. Some of the material may already be in the public domain, and some parts of the work may expire sooner than others.
Even if some of the material in the derivative work is in the public domain and free for use, this does not mean that the "new" material added to it can be used without permission from the owner of copyright in the derivative work. It may be necessary to compare editions to determine what is free to use and what is not.
Ownership of rights in the material included in a derivative work and in the preexisting work upon which it may be based may differ, and permission obtained from the owners of certain parts of the work may not authorize the use of other parts.
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